I'm reading the "Mathematical typesetting table" from MS which has been incorporated into the Standard for Open Type Fonts recently.
In the section
MATH – Table organization and structure there is a paragraph I couldn't understand:
When designing a MATH table, device tables may be specified for many values used for positioning elements of a formula, suggesting many device corrections. However, a math handling engine may not permit those corrections to accumulate. This accumulation will result in formula dimensions that are significantly different from scaled-down dimensions of the same formula rendered on a high-resolution device. Therefore, accumulation is undesirable and leads to inconsistencies between screen and print versions, as well as possible clipping.
What do they mean by
corrections to accumulate above?